Gene behind severe skin reaction to common epilepsy drug identified

Researchers have identified a gene responsible for severe skin reaction to a common epilepsy drug.

Carbamazepine is commonly used to treat patients with epilepsy and other diseases such as depression and trigeminal neuralgia.

Although successful in treating the majority of patients, it can cause side-effects that range from a mild skin irritation to severe blistering of the whole body.

Taiwanese researchers had earlier identified a gene that predisposes Asian patients to the skin condition. However, the gene could not predict the reaction in Caucasian people.

Scientists from the University of Liverpool, in collaboration with the Wellcome Trust Sanger Institute, screened more than a million variants in DNA across the human genome to understand why some patients are more prone to the drug”s side-effects than others.

They found the gene, called HLA-A*3101, increases the risk of developing a reaction to the drug from 5 percent to 26 percent in Caucasian patients.

Researchers are now working with clinicians and drug regulators to investigate how these new findings can translate into clinical practice.

“For the first time we have found a significant link between the drug and the skin condition in Caucasian people that also complements the findings in Asian patients. We can now begin to work with clinicians and regulators to maximise the benefits of the drug and minimise the side-effects,” said Prof Munir Pirmohamed.